CVE-2026-73576

medium

Description

In Zimbra Collaboration (ZCS) before 10.1.17, weak cryptographic key generation vulnerability exists in the OnlyOffice integration. The zimbraDocumentEditingJwtSecret is generated using an insecure random number generator, resulting in insufficient entropy. An attacker who obtains a JWT signed with the generated secret may be able to recover the JWT signing secret through offline brute-force, potentially enabling JWT forgery.

References

https://wiki.zimbra.com/wiki/Zimbra_Security_Advisories

https://wiki.zimbra.com/wiki/Zimbra_Responsible_Disclosure_Policy

Details

Source: Mitre, NVD

Published: 2026-08-13

Updated: 2026-08-28

Risk Information

CVSS v2

Base Score: 6.8

Vector: CVSS2#AV:N/AC:L/Au:S/C:N/I:C/A:N

Severity: Medium

CVSS v3

Base Score: 6.5

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N

Severity: Medium

EPSS

EPSS: 0.00188